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== Promise v0.1.0 ==

An implementation of promises and futures for Javascript.  To use, just
grab the `Promise.js` file from the build directory.  It works as a script
tag and as a Node module.


=== new Promise() ===

Creates a new promise object.  A promise can be in one of three states:  pending,
fulfilled, or rejected.  A promise that is either fulfilled or rejected is called 
"resolved".  You can query the promise for it's resolved value (which might be the
expected value or an error) by using its associated future.


=== promise.resolve(value) ===

Resolves the promise with the specified value.  If the provided value is a 
rejection, then the promise is "rejected".  Otherwise the promise is "fulfilled".
If the promise has already been resolved, then this function will throw an error.


=== promise.reject(error) ===

Rejects the promise with the specified error.  If the promise has already been
resolved, then this function will throw an error.


=== promise.future ===

The future associated with the promise.  The future can be used to query the
resolved value of the promise.


=== future.then(onSuccess, onFail = null) ===

Registers callbacks that will execute when the future's value is available.
If the future results in an error, then the `onFail` callback will be called.
Otherwise the `onSuccess` callback will be called.  All callbacks execute
asynchronously.

Returns a future for the transformation applied by the callback functions.


=== Promise.when(valueOrFuture) ===

Returns a future for the specified argument.  If the argument is itself a
future then it will be returned without modification.


=== Promise.reject(error) ===

Returns a future for the specified error.


=== Promise.whenAll(array) ===

Returns a future for an array which contains the eventual value for every
future in the input array.  If any future in the input array fails, then
the returned future fails.


=== Promise.whenAny(array) ===

Returns a future for the first resolved future in the input array.